1. Field of the Invention
The present invention relates to a data processing apparatus and data processing method that are used for image processing.
2. Description of the Related Art
A plurality of ink ejection nozzles, each being designed so as to eject the same ink volume, actually eject different ink volumes due to manufacturing variations. Accordingly, if the plurality of ejection nozzles are used to form an image on a print medium with the same number of dots, an even density may occur due to, for example, manufacturing variations.
In order to solve the problem of such an uneven density, Japanese Patent Laid-Open No. H10-013674 (1998) discloses a head-shading technique in which information on an ink volume ejected from each of ink ejection nozzles is obtained and on the basis of this information the number of print dots is changed.
The head-shading technique can solve the problem of an uneven density in each ink color by changing the number of print dots, but cannot solve the problem of an uneven color of a color formed by two or more ink colors due to an ink ejection volume of each of the ink ejection nozzles.